Cardiac adaptation in asphyxiated infants treated with therapeutic hypothermia.

BACKGROUND: Hypoxic ischemic encephalopathy (HIE) affects  one to two newborns per 1,000 live births and oftentimes involves multi-organ insult. The objectives were to assess the evolution of cardiac function in infants with HIE treated with therapeutic hypothermia using echocardiography (ECHO). METHODS: Archived data during the period 2010-2016 was assessed. Amongst the infants with baseline ECHO assessments, a sub-cohort which had assessments in all the three phases (baseline/pre-active cooling [T1], cooling [T2] and rewarming [T3]) was analyzed separately. RESULTS: Thirty three infants formed part of the overall cohort, the gestation and birthweight were 39.6 ± 1.6 weeks and 3306 ± 583 g, respectively. Baseline (T1) information noted impaired cardiac performance (right ventricle stroke volume 1.08 ± 0.04 ml/kg, fractional area change [FAC] 24 ± 0.5% and tricuspid annular peak systolic excursion [TAPSE] 7.46 ± 0.11mm). Serial information was available for 24 of 33 infants. Cardiac function improved significantly between the cooling and the re-warming kphases. This included changes in right ventricular output (127 ± 34 vs 164 ± 47 ml/kg/min, p <0.01) and FAC (20 ± 3 vs 28 ± 2%, p<0.01). Pairwise comparisons for fractional shortening did not show significant changes. From the cooling to the rewarming phase, maximum change was noted in FAC (26.3 ± 9.8%) while minimum change was noted in fractional shortening (median, interquartile range) of 4.6% (1.4, 9.1). Significant correlation between TAPSE and time to peak velocity as a proportion of right ventricular ejection time was noted (r2 = 0.68, p <0.001). CONCLUSIONS: In infants with moderate to severe HIE, cardiac function evolves during various phases of therapeutic hypothermia. Low output state during cooling may be due to a combination of the disease state (HIE) and cooling therapy.

Factors associated with the orthopaedic surgeon's decision to recommend total joint replacement in hip and knee osteoarthritis: an international cross-sectional study of 1905 patients.

OBJECTIVE: To determine factors associated with orthopaedic surgeons' decision to recommend total joint replacement (TJR) in people with knee and hip osteoarthritis (OA). DESIGN: Cross-sectional study in eleven countries. For consecutive outpatients with definite hip or knee OA consulting an orthopaedic surgeon, the surgeon's indication of TJR was collected, as well as patients' characteristics including comorbidities and social situation, OA symptom duration, pain, stiffness and function (Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC]), joint-specific quality of life, Osteoarthritis Research Society International (OARSI) joint space narrowing (JSN) radiographic grade (0-4), and surgeons' characteristics. Univariable and multivariable logistic regressions were performed to identify factors associated with the indication of TJR, adjusted by country. RESULTS: In total, 1905 patients were included: mean age was 66.5 (standard deviation [SD], 10.8) years, 1082 (58.0%) were women, mean OA symptom duration was 5.0 (SD 7.0) years. TJR was recommended in 561/1127 (49.8%) knee OA and 542/778 (69.7%) hip OA patients. In multivariable analysis on 516 patients with complete data, the variables associated with TJR indication were radiographic grade (Odds Ratio, OR for one grade increase, for knee and hip OA, respectively: 2.90, 95% confidence interval [1.69-4.97] and 3.30 [2.17-5.03]) and WOMAC total score (OR for 10 points increase: 1.65 [1.32-2.06] and 1.38 [1.15-1.66], respectively). After excluding radiographic grade from the analyses, on 1265 patients, greater WOMAC total score was the main predictor for knee and hip OA; older age was also significant for knee OA. CONCLUSION: Radiographic severity and patient-reported pain and function play a major role in surgeons' recommendation for TJR.

Reaching the theoretical resonance quality factor limit in coaxial plasmonic nanoresonators fabricated by helium ion lithography.

Optical antenna structures have revolutionized the field of nano-optics by confining light to deep subwavelength dimensions for spectroscopy and sensing. In this work, we fabricated coaxial optical antennae with sub-10-nanometer critical dimensions using helium ion lithography (HIL). Wavelength dependent transmission measurements were used to determine the wavelength-dependent optical response. The quality factor of 11 achieved with our HIL fabricated structures matched the theoretically predicted quality factor for the idealized flawless gold resonators calculated by finite-difference time-domain (FDTD). For comparison, coaxial antennae with 30 nm critical dimensions were fabricated using both HIL and the more common Ga focus ion beam lithography (Ga-FIB). The quality factor of the Ga-FIB resonators was 60% of the ideal HIL results for the same design geometry due to limitations in the Ga-FIB fabrication process.

Helium ion microscopy for high-resolution visualization of the articular cartilage collagen network.

The articular cartilage collagen network is an important research focus because network disruption results in cartilage degeneration and patient disability. The recently introduced helium ion microscope (HIM), with its smaller probe size, longer depth of field and charge neutralization, has the potential to overcome the inherent limitations of electron microscopy for visualization of collagen network features, particularly at the nanoscale. In this study, we evaluated the capabilities of the helium ion microscope for high-resolution visualization of the articular cartilage collagen network. Images of rabbit knee cartilage were acquired with a helium ion microscope; comparison images were acquired with a field emission scanning electron microscope (FE-SEM) and a transmission electron microscope (TEM). Sharpness of example high-resolution helium ion microscope and field emission scanning electron microscope images was quantified using the 25-75% rise distance metric. The helium ion microscope was able to acquire high-resolution images with unprecedented clarity, with greater sharpness and three-dimensional-like detail of nanoscale fibril morphologies and fibril connections, in samples without conductive coatings. These nanoscale features could not be resolved by field emission scanning electron microscopy, and three-dimensional network structure could not be visualized with transmission electron microscopy. The nanoscale three-dimensional-like visualization capabilities of the helium ion microscope will enable new avenues of investigation in cartilage collagen network research.

Pulmonary embolism in sickle cell disease: a case-control study.

INTRODUCTION: A pulmonary embolism (PE) is a leading cause of mortality in hospitalized patients, yet the prevalence of PE in sickle cell disease (SCD) and its relation to disease severity or intrinsic hypercoagulability are not established. METHODS: We estimated inpatient PE incidence and prevalence among SCD and non-SCD populations in Pennsylvania, and compared severity of illness and mortality, using Pennsylvania Health Care Cost Containment Council (PHC4) discharge data, 2001-2006. Risk factors for PE were assessed in a case-control study of discharges from the University of Pittsburgh Medical Archival Records System (MARS). RESULTS: The incidence of inpatient PE was higher in the SCD PA population than in the non-SCD Pennsylvania population, 2001-2006. The PE prevalence among SCD discharges ≤ 50 years of age, 0.57%, was similar to that in non-SCD Pennsylvania discharges, 0.60%, and unchanged after adjustment for race. Among SCD discharges, those developing PE were significantly older, with a longer length of stay, greater severity of illness and higher mortality, P < 0.001, than SCD without a PE. Among PE discharges, SCD had a similar severity of illness, P = 0.77, and mortality, P = 0.39, but underwent fewer computerized tomographic scans, P = 0.006, than non-SCD with PE. In the local case-control study, no clinical or laboratory feature was associated with PE. CONCLUSIONS: The incidence of PE is higher and chest computed tomography (CT) utilization is lower in SCD than non-SCD inpatients, suggesting that PE may be under-diagnosed.

Acute life-threatening extrinsic allergic alveolitis in a paint controller.

BACKGROUND: Occupational diisocyanate-induced extrinsic allergic alveolitis (EAA) is a rare and probably underestimated diagnosis. Two acute occupational EAA cases have been described in this context, but neither of them concerned hexamethylene diisocyanate (HDI) exposure. AIMS: To investigate the cause of a life-threatening EAA arising at work in a healthy 30-year-old female paint quality controller. METHODS: Occupational medical assessment, workplace evaluation, airborne and biological monitoring and immunodermatological tests. RESULTS: Diagnosis of EAA relied on congruent clinical and radiological information, confirmed occupational HDI exposure and positive IgG antibodies and patch tests. The patient worked in a small laboratory for 7 years, only occasionally using HDI-containing hardeners. While working with HDI for 6 h, she developed breathlessness, rapidly progressing to severe respiratory failure. Workplace HDI airborne exposure values ranged from undetectable levels to 4.25 p.p.b. Biological monitoring of urinary hexamethylene diamine in co-workers ranged from <1.0 to 15.4 µg/g creatinine. Patch tests 8 months later showed delayed skin reaction to HDI at 48 h. Subsequent skin biopsy showed spongiotic dermatitis with infiltration of CD4(+) and CD8(+) T cells. CONCLUSIONS: We believe this is the first reported case of acute life-threatening EAA following exposure to HDI. Low concentrations of airborne HDI and relatively high urinary hexamethylene diamine suggest significant skin absorption of HDI could have significantly contributed to the development of this acute occupational EAA.

Efficient in vivo microRNA targeting of liver metastasis.

Targeting oncogenic microRNAs (miRNAs) is emerging as a promising strategy for cancer therapy. In this study, we provide proof of principle for the safety and efficacy of miRNA targeting against metastatic tumors. We tested the impact of targeting miR-182, a pro-metastatic miRNA frequently overexpressed in melanoma, the in vitro silencing of which represses invasion and induces apoptosis. Specifically, we assessed the effect of anti-miR-182 oligonucleotides synthesized with 2' sugar modifications and a phosphorothioate backbone in a mouse model of melanoma liver metastasis. Luciferase imaging showed that mice treated with anti-miR-182 had a lower burden of liver metastases compared with control. We confirmed that miR-182 levels were effectively downregulated in the tumors of anti-miR-treated mice compared with tumors of control-treated mice, both in the liver and in the spleen. This effect was accompanied by an upregulation of multiple miR-182 direct targets. Transcriptional profiling of tumors treated with anti-miR-182 or with control oligonucleotides revealed an enrichment of genes controlling survival, adhesion and migration modulated in response to anti-miR-182 treatment. These data indicate that in vivo administration of anti-miRs allows for efficient miRNA targeting and concomitant upregulation of miRNA-controlled genes. Our results demonstrate that the use of anti-miR-182 is a promising therapeutic strategy for metastatic melanoma and provide a solid basis for testing similar strategies in human metastatic tumors.

Building bioinformatics capacity in West Africa.

African scientists need more bioinformatics training in order to make innovative contributions to global biotechnology. To address the bioinformatics skills gap in West Africa, various training initiatives have been established in the sub-region. We present the activities of the West African Biotechnology Workshops (http://www.wabw.org/) in the past three years, and report on a symposium on bioinformatics and applied genomics in West Africa. To establish and sustain regional and national networks, stronger and increased government commitment by way of financial and infrastructural support for bioinformatics capacity building in West Africa is required.

Inhibitory effects of retinoic acid metabolism blocking agents (RAMBAs) on the growth of human prostate cancer cells and LNCaP prostate tumour xenografts in SCID mice.

In recent studies, we have identified several highly potent all-trans-retinoic acid (ATRA) metabolism blocking agents (RAMBAs). On the basis of previous effects of liarozole (a first-generation RAMBA) on the catabolism of ATRA and on growth of rat Dunning R3227G prostate tumours, we assessed the effects of our novel RAMBAs on human prostate tumour (PCA) cell lines. We examined three different PCA cell lines to determine their capacity to induce P450-mediated oxidation of ATRA. Among the three different cell lines, enhanced catabolism was detected in LNCaP, whereas it was not found in PC-3 and DU-145. This catabolism was strongly inhibited by our RAMBAs, the most potent being VN/14-1, VN/50-1, VN/66-1, and VN/69-1 with IC50 values of 6.5, 90.0, 62.5, and 90.0 nM, respectively. The RAMBAs inhibited the growth of LNCaP cells with IC50 values in the microM-range. In LNCaP cell proliferation assays, VN/14-1, VN/50-1, VN/66-1, and VN/69-1 also enhanced by 47-, 60-, 70-, and 65-fold, respectively, the ATRA-mediated antiproliferative activity. We then examined the molecular mechanism underlying the growth inhibitory properties of ATRA alone and in combination with RAMBAs. The mechanism appeared to involve the induction of differentiation, cell-cycle arrest, and induction of apoptosis (TUNEL), involving increase in Bad expression and decrease in Bcl-2 expression. Treatment of LNCaP tumours growing in SCID mice with VN/66-1 and VN/69-1 resulted in modest but statistically significant tumour growth inhibition of 44 and 47%, respectively, while treatment with VN/14-1 was unexpectedly ineffective. These results suggest that some of our novel RAMBAs may be useful agents for the treatment of prostate cancer.

Development and validation of a new bitumen fume generation system which generates polycyclic aromatic hydrocarbon concentrations proportional to fume concentrations.

Bitumen fumes emitted during road paving and roofing contain polycyclic aromatic compounds (PACs) of potential health concern. Little information is available for an experimental device devoted to inhalation experiments with animals exposed to bitumen fumes, and in all studies the systems were never validated for a range of fume concentrations, which prohibited their use for toxicological concentration-effect studies. Therefore, the purpose of this study was to validate a new experimental device able to generate bitumen fumes at different total particulate matter (TPM) concentrations with a linear correlation between TPM and the concentrations of different PACs, thus allowing toxicological dose-response studies with fumes representative of those in the field. Atmosphere samples collected from an animal exposure chamber allowed the determination of TPM, toluene soluble matter, polycyclic aromatic hydrocarbons (PAHs) and semi-volatiles. The particulate size distributions were determined in order to assess the deposition pattern in the respiratory tract. The temperature of 170 degrees C was chosen by analogy with the upper range of the temperature used during paving operations. The temperature of the air passing over the fume emission area was regulated to 20 degrees C and stirring of the heated bitumen was restricted to 90 r.p.m. The data show that the objective of developing a static fume generation system that reproducibly produces fumes in the inhalation chamber for specified target concentrations (TPM) were successful. The within-day variation coefficients for TPM were between 2.5 and 6.1%. The day-to-day variations for TPM concentration were between 4.1 and 5.8%. The concentrations of the 4-5 ring PAHs and the polycyclic aromatic sulphur heterocycles were proportional to the TPM concentration. The 2 and 3 ring PAH concentrations showed a deviation from proportionality with the TPM, probably due to their re-evaporation during sampling. The mass median aerodynamic diameter of airborne particles varied from 1.4 micro m at a fume concentration of 5 mg/m(3) to 3.2 micro m at 100 mg/m(3). In conclusion, this equipment was suitable for nose-only inhalation studies in the 5-100 mg/m(3) range of TPM. Bitumen fumes were generated with a good reproducibility under well-controlled conditions. Finally, the PAH profiles from atmospheric samples were in good agreement with those measured during road paving.

A spectrophotometric method for the determination of organic soluble matter in bitumen fumes.

A UV spectrophotometric procedure was validated for the determination of organic soluble matter in bitumen fumes collected by filtration technique. Ultrasonic extraction was carried out with toluene, an efficient extraction solvent for polycyclic aromatic hydrocarbons, followed by UV absorbance measurements at 320 nm. A calibration curve is plotted from the same set of samples determined by classical weighing method. Further determinations can also be made using the slope factor of the calibration curve. The procedure presents obvious simplicity and rapidity advantages and is less prone to losses than the measurements of weight. Inter-method comparisons of samples collected from experimental laboratory-generated penetration bitumen fumes commonly used in road paving showed that the three available procedures-weighing, infrared, and UV--described for the determination of organic soluble matter yield equivalent results.

Transforming growth factor beta 1 dysregulation in a human oral carcinoma tumour progression model.

A human oral tumour progression model was established that consists of normal epithelial cells and three cell lines representing stages from dysplastic to metastatic cells. To investigate the impact of exogenous transforming growth factor-beta 1 on this model system, we analysed the responsiveness of those cells to transforming growth factor-beta 1 and explored the potential mechanism underlying the transforming growth factor-beta 1 activity. We found that the growth of all cell types, regardless of their stage of tumour progression, is inhibited by transforming growth factor-beta 1, although to different degrees. Transforming growth factor-beta 1 induced the expression of cyclin-dependent kinase inhibitors p15(INK4B), p21WAF1/(CIP1) and p27(KIP1). In contrast, transforming growth factor-beta 1 was found to stimulate the invasive potential of one cell type that represents the most advanced stage of tumour phenotype, suggesting that the impact of transforming growth factor-beta 1 on functional features of tumour cells other than cellular proliferation may play a significant role in the process of oral tumour progression.

Intron-dependent stimulation of marker gene expression in cultured insect cells.

We tested in a systematic fashion the effect of an intron on the level of luciferase expression in cultured C6/36 Aedes albopictus cells. The intron was inserted in both orientations, upstream and downstream of the luciferase coding region in two different luciferase expression vectors. The two parental luciferase expression vectors differed only in their promoters, one containing the Drosophila melanogaster actin5C promoter and the other the Autographa californica nuclear polyhedrosis virus hr5/ie1 enhancer/promoter. All resulting intron-containing constructs were tested for their ability to express luciferase in transient assays following electroporation into C6/36 cells. We found that the introns stimulate luciferase expression between twelve and sixtyfold, depending on the promoter. Enhanced expression was only seen when the intron was present in the correct orientation upstream of the luciferase ORF. When the 3' splice sites of the enhanced intron-containing constructs were mutated, the expression level dropped back to below the level of the intronless parental constructs, suggesting that the intron-dependent stimulation of luciferase expression is depending on splicing and is not due to other effects the intron may have on transcription or translation. The luciferase transcripts of all constructs were analysed by reverse transcription, PCR amplification and sequencing, and the results show a perfect correlation between efficient splicing of the intron and elevated levels of luciferase expression. Our findings have the potential to be very useful for boosting expression of foreign proteins in the widely used baculoviral or non-viral systems in insect cells.

Comparative effects of red blood cell transfusion and increasing blood flow on tissue oxygenation in oxygen supply-dependent conditions.

Red blood cell (RBC) transfusion is usually administered to improve oxygen delivery (DO(2)) in order to sustain tissue oxygen demand. However, this practice is not supported by firm clinical or experimental data. Using a randomized two-period crossover design, this study compared the efficacy of "fresh" RBC transfusion and increased blood flow to restore tissue oxygenation in oxygen supply-dependent conditions. In 12 ketamine-anesthetized mongrel dogs submitted to nonpulsatile normothermic cardiopulmonary bypass, DO(2) was reduced by a progressive decrease in pump flow. DO(2) dependency was defined as an O(2) uptake (V O(2)) decrease by more than 15% from baseline value. Then, intervention consisted of a 40% increase in DO(2) obtained either by transfusion of "fresh" dog's RBC (stored < 3 d) or by increase in pump flow. Animals received both interventions sequentially in a random order, while O(2) saturation was maintained constant. In O(2) supply-dependent conditions, rising pump flow from 1.6 +/- 0.4 to 2.7 +/- 0.7 L/ min increased DO(2) from 5.4 +/- 1.1 to 9.0 +/- 1.3 ml/kg/min (p < 0.01) and V O(2) from 3.5 +/- 0.4 to 4.1 +/- 0.5 ml/kg/min (p = 0.02). "Fresh" RBC transfusion, which increased the hemoglobin concentration from 6.4 +/- 0.9 to 11.1 +/- 1.3 g/dl, increased DO(2) from 5.4 +/- 1.2 to 9.0 +/- 1.4 ml/kg/min (p < 0.01) and V O(2) from 3.6 +/- 0.4 to 4.1 +/- 0.5 ml/kg/min (p = 0.02). There was no difference in V O(2) resulting from both interventions. In oxygen supply-dependent conditions, "fresh" RBC transfusion and increased blood flow are equally effective in restoring tissue oxygenation.

Chemopreventive effects of green tea polyphenols correlate with reversible induction of p57 expression.

Green tea polyphenols are known to induce apoptosis in certain types of tumor cells. However, the mechanism(s) that enables normal cells to evade the apoptotic effect is still not understood. In this study, Western blot analysis combined with cycloheximide treatment was used to examine the effects of green tea polyphenols on the expression levels of p57, a cyclin-dependent kinase and apoptosis inhibitor, in normal human keratinocytes and in the oral carcinoma cell lines SCC25 and OSC2. The results showed that the most potent green tea polyphenol, (-)-epigallocatechin-3-gallate (EGCG), induced p57 in normal keratinocytes in a dosage- and time-dependent manner, while the levels of p57 protein in oral carcinoma cells were unaltered. The differential response in p57 induction was consistent with the apoptosis status detected by annexin V assay. The data suggest that the chemopreventive effects of green tea polyphenols may involve p57-mediated cell cycle regulation in normal epithelial cells.

Development of an analytical method for the simultaneous determination of 15 carcinogenic polycyclic aromatic hydrocarbons and polycyclic aromatic nitrogen heterocyclic compounds. application to diesel particulates.

A new method enabling the determination of 15 priority carcinogenic polyaromatic compounds (PAC) proposed by the US National Toxicology Program (NTP) has been developed and applied to diesel exhaust particulates (DEP). The clean-up procedure consists of solid-phase extraction (SPE) and HPLC fractionation on silica phases followed by liquid-liquid extraction and chromatography on a polyvinylbenzene copolymer column. The method gives good recoveries for all PAC studied except dibenzo[a,j]acridine and dibenzo[a,h]pyrene, for which recovery values are below 80%. The use of GC-MS ion trap and its capacity to achieve single-ion storage enhanced the sensitivity of the method, enabling the detection of high-molecular-weight PAH in the low ng g(-1) concentration range. Intermediate polarity GC columns, e.g. BPX-50 or equivalent, enabled better separation, when applied to DEP analysis, than the generally used DB-5 apolar phase. This is observed mainly for separation of isomeric compounds belonging to the benzofluoranthene and dibenzopyrene families. The application of this method to DEP sampled from the exhaust of a diesel engine and in confined locations such as a tunnel has shown that all PAH of the NTP list could be detected, except dibenzo[a,h]pyrene. No dibenzacridine or dibenzocarbazole could be detected in such matrices. The method is sufficiently sensitive to be applicable to environmental exposure measurements in occupational health surveys.

Identification and characterization of a 315-base pair enhancer, located more than 55 kilobases 5' of the apolipoprotein B gene, that confers expression in the intestine.

We recently reported that an 8-kilobase (kb) region, spanning from -54 to -62 kb 5' of the human apolipoprotein B (apoB) gene, contains intestine-specific regulatory elements that control apoB expression in the intestines of transgenic mice. In this study, we further localized the apoB intestinal control region to a 3-kb segment (-54 to -57 kb). DNaseI hypersensitivity studies uncovered a prominent DNaseI hypersensitivity site, located within a 315-base pair (bp) fragment at the 5'-end of the 3-kb segment, in transcriptionally active CaCo-2 cells but not in transcriptionally inactive HeLa cells. Transient transfection experiments with CaCo-2 and HepG2 cells indicated that the 315-bp fragment contained an intestine-specific enhancer, and analysis of the DNA sequence revealed putative binding sites for the tissue-specific transcription factors hepatocyte nuclear factor 3beta, hepatocyte nuclear factor 4, and CAAT enhancer-binding protein beta. Binding of these factors to the 315-bp enhancer was demonstrated in gel retardation experiments. Transfection of deletion mutants of the 315-bp enhancer revealed the relative contributions of these transcription factors in the activity of the apoB intestinal enhancer. The corresponding segment of the mouse apoB gene (located -40 to -83 kb 5' of the structural gene) exhibited a high degree of sequence conservation in the binding sites for the key transcriptional activators and also exhibited enhancer activity in transient transfection assays with CaCo-2 cells. In transgenic mouse expression studies, the 315-bp enhancer conferred intestinal expression to human apoB transgenes.